This specification includes a microfiche appendix in compliance with 37 C.F.R. xc2xa71.96(c) consisting of two (2) slides and 166 frames.
1. Field of the Invention
The present invention relates generally to a frozen product preparation apparatus and, more particularly, to a cryogenic processor for liquid feed preparation of a free-flowing frozen product.
2. Description of the Prior Art
Sales of ice cream and frozen yogurt products have risen dramatically in recent years, and applicants herein have captured a portion of this product market through the development of a unique novelty ice cream, frozen yogurt and ice product in the form of beads. This product, marketed under the trademarks xe2x80x9cDippin"" Dots(copyright)xe2x80x9d and xe2x80x9cIce Cream of the Future(copyright)xe2x80x9d, has become very popular in specialty stores, at fairs and theme parks, and through vending machines.
Applicants have proprietary rights in the method of preparing and storing the product pursuant to U.S. Pat. No. 5,126,156, issued Jun. 30, 1992, herein incorporated by reference, as well as rights associated with improvements pursuant to U.S. Pat. No. 5,664,422, issued Sep. 9, 1997, and U.S. Pat. No. 6,000,229, issued Dec. 14, 1999, herein incorporated by reference. As is generally described therein, the patented method involves delivering flavored liquid dairy and other alimentary compositions to a feed tray and then dripping the composition into a freezing chamber. The feed tray comprises a plurality of orifices through which liquid composition passes to fall into the freezing chamber, either in the form of droplets or liquid streams, which streams break into droplets before freezing. Each orifice may also have a corresponding feed dropper, which is downwardly disposed in relation to the tray such that the liquid composition passes from the tray through an orifice and then through an associated feed dropper where a droplet or liquid stream is formed. The orifices or combination of orifices and feed droppers will hereinafter be referred to collectively as feed assemblies.
The falling droplets of liquid composition freeze rapidly (i.e., flash freeze) in the freezing chamber due to the presence of both gaseous and liquid refrigerant in the area between the orifices and the bottom of the freezing chamber, thereby forming solid beads of flavored ice cream, yogurt or other alimentary products, such as flavored ice. More specifically, as droplets of liquid free fall through a gaseous region of the freezing chamber, and before the droplets contact the liquid refrigerant, the outer spheres of the droplets form a thin frozen shell. This thin frozen shell serves to protect the spherical shape of the droplets as they impact the surface of the liquid refrigerant. The remainder of the droplets freeze completely as they pass through the liquid refrigerant, and before reaching the bottom of the freezing chamber. The frozen beads are removed from the freezing chamber and packed for distribution and later consumption.
It should be appreciated that the cryogenic processor used for preparing the above-described beaded ice-cream is a relatively sophisticated apparatus that should be tightly controlled for proper operation. For example, the liquid refrigerant preferably used is liquid nitrogen, which has an extremely high evaporation rate. It is typically desired to maintain approximately 19-21 inches of separation between the surface of the liquid nitrogen and the feed tray. If this separation distance is too small, then the liquid droplets may not have sufficient time during their free-fall from the feed tray to form the desired spherical shape. If the separation distance is too large then the impact of the droplets with the surface of the liquid nitrogen may become undesirably large. Accordingly, the introduction of liquid nitrogen into the freezing chamber should be closely controlled.
In addition, the rate at which liquid composition passes through the orifices of the feed tray and the size of the droplets is controlled by the level of liquid composition maintained in the feed tray. As a result, the delivery of the liquid composition to the feed tray should be tightly monitored and controlled.
In addition to the desire to closely control operation parameters of the cryogenic processor, other improvements are desired. For example, it is often desired to manufacture beaded ice-cream of various flavors. Often, unique flavors are created by mixing certain fundamental or base flavors. One way this may be accomplished is by manufacturing a first base flavor, then manufacturing a second base flavor, then mixing the two beaded ice-cream products. This approach, however, requires that piping and other machinery be cleaned between xe2x80x9cbatchesxe2x80x9d (i e., flavor changes). Another disadvantage of this approach is the added step of mixing the beaded form of the two base flavors.
Another way that a multi-flavor product may be created is by mixing the liquid form of the base flavors in appropriate proportions, before delivery to the feed tray. This approach, however, also requires that piping and other machinery be cleaned between batches.
Accordingly, it is desired to provide an improved cryogenic processor for preparing a unique, beaded ice-cream product.
Certain objects, advantages and novel features of the invention will be set forth in part in the description that follows and in part will become apparent to those skilled in the art upon examination of the following or may be learned with the practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out in the appended claims.
To achieve the advantages and novel features, the present invention is generally directed to a cryogenic processor for liquid feed preparation of a free-flowing frozen product comprising. In accordance with one aspect of the invention, the cryogenic processor includes a freezing chamber having a substantially conical shape, at least one feed tray overlying the freezing chamber arranged and adapted to receive liquid composition from a delivery source, the tray having a plurality of orifices for the discharge of uniformly sized droplets of the composition from the feed tray, whereby the droplets are delivered by gravity into the freezing chamber there-below. The cryogenic processor also includes at least one sensor associated with the feed tray for determining a depth of liquid composition in the feed tray, at least one valve associated with a liquid composition delivery line, the valve being configured to control the rate at which liquid composition is delivered from the delivery source to the feed tray, and a controller responsive to the at least one sensor for controlling a position of the valve, and therefore the rate at which liquid composition is delivered from the delivery source to the feed tray.
In accordance with another aspect of the invention, a method is provided for feeding liquid composition to a freezing chamber containing a refrigerant to form beads of frozen product. In accordance with this aspect of the invention, the method monitoring a level of liquid composition in each section of a multi-partition feed tray, closely controlling the delivery a liquid feed composition from a source to each section of the feed tray, discharging the liquid feed composition from each section of the feed tray through orifices in the form of droplets, via gravity, into a freezing chamber disposed below the orifices, monitoring a level of liquid refrigerant in a freezing chamber, and closely controlling the delivery of liquid refrigerant to the freezing chamber, in response to the step of monitoring the level of liquid refrigerant.